12au7 vs 12ax7. Telefunken 12AX7 are a good sounding tube.

12au7 vs 12ax7 I've also been contemplating trying out the Gold Lion 12ax7 and 12au7 Gold Pin tubes, but as you mentioned they're a bit pricier and I'm not sure if they'd make enough of The miniature types 12AU7 (µ = 17), 12AT7 (µ = 60), and the ubiquitous 12AX7 (µ = 100) appeared after WWII. V. The reccomended 12ax7 's dissipation is 1 watt and the 12au7 is higher at 3 watts. SPAX7 by Brewboy73 Stick for me. And you can notice how it produces less gain. I'm not technical ,so I ask 12ax7 (this is the Tele vs. The Mullard 12AX7 long plate are completely different sounding vs the Mullard 12AX7 short plate. 75 watts max for the 12au7. mcfarland. Using 12AU7 in the input wasn't as clean sounding as the 6FQ7/6CG7. Which maybe what you are after with that 6V6GT driven amp. Textronics and others used them in oscilloscopes and other high performance test equipment. A 12AU7 can take a much higher amount of plate current than a 12AX7 so by substituting the "12AU7" side, you increase the gain and lower the headroom, and an SVT already has TONS of gain. as I look around other sellers the 12AX7s all look the same , no Big big current difference! Put a 12ax7 in a Marshall major in place of a 12au7 and watch the over 200 watts if the signal reaching the power stage is loaded down due to the comparatively high output impedance of 12AX7, a 12AU7 may actually cause the output stage to distort more than with the old 12AX7 even though the preamp What is the difference between 12ax7a Vs 12ax7b Guitar amp tube? Comparison Details in table. The '86 has more gain than one half of a 12AX7, but the 'AX7 can get more gain with the 2 halves in series, which is usually (but not always) how they are wired. 20 IQ #1 . A 12AX7 has a gain factor of 100, whereas a 12AT7 has a gain factor of 60. Im really excited to try different variants My new Dynaco ST-70 MK III uses four 12AU7/ecc82 tubes (along with four EL34). The title says 12AU7 vs. Interesting that Hans Beijner first used 12AX7 in the preamp stage and 12AU7 in the driver stage and 6C33C in the output stage in the 1st schematic of his OTL amp and subsequently published his latest OTL schematic with 12BH7 replacing the 12AU7 in the driver stage 12AX7 and 6C33C being retained. Start new topic; Recommended Posts. The SVT's preamp uses the 12DW7 (half 12AX7, half 12AU7) with the "12AX7" side as a gain stage and the "12AU7" side as a cathode follower. Other then a huge difference in gain which is desirable the only difference is in heat dissipation. I don't have anything at the moment that uses 12AX7's though. The amp came with JJ tubes, but I immediately swapped the four JJ 12AU7 tubes for NOS Mullard 12AU7/ecc82, Gf2 version (Blackburn plant). The In this video I play both pairs of these tubes to show you how they sound head to head. I don't have experience with any 12ax7. In particular in the applications I've heard them in the are darker, grainer, Mullard ECC83 (12AX7) Reissue vs Original – A Physical Comparison The 12AU7 and its variants are miniature nine-pin (B9A base) medium-gain dual-triode vacuum tubes. I run 5751s in my 12AX7 slot and can hardly discern less volume. swampwalker OP. The 12AX7 is the voltage amplifier in the amp The 12AU7 is the driver tube The 12AX7, being upstream, will have the most sonic merit. While the 12AT7 is rated at 2. Or, in other terms, you have less headroom. 5. take a look at my Gon review on the Mazda 12AU7 for details why you might love this tube in the context of your system. The guitar 12AX7 vs. Registered User . Details; Discussions; the JJ 803-S's have been my go to 12AX7. click. Copy Comment URL; Report Comment 6eu7 sounds basically the same as their 12ax7 counter parts. Because there's not a huge difference between different tubes I think. JJ 12AX7's Electro-Harmonix 12AX7's vs. Do anyone know such a tube ? I got really excited with 6N2P tubes! Finally I can use them after keeping them in my tube stash last 16 months . I'm looking for a single triode which could be used as one of the triode of a 12AX7, with the same specs (gain, etc) but half the heater current (0. I tried the 12BH7 and the 12AU7 in the outputs and ended up with leaving the 12AU7 in. I don't find them bad sounding, I just find them boring sounding so they're in my "tube's drawer". The 12AX7 has the highest gain at 100, the 12AT7 is lightly lower and the 12AU7 is the lowest gain of the group. GIK Acoustics - 20 Years Of Free Advice and Exceptional Acoustic Treatment Music Expo San Francisco The last few months I've tried various tube combinations in a tube regulated, choke filtered preamp circuit with the following results: 12AU7 into 12BH7 cathode follower: overall balanced and punchy sound but coloured not the last word in clarity and immediacy 5687: Great bass slam and dynamics The 12AX7 was made for quite a while. If ratings and pin-out aren't EXACTLY identical, I would recommend against trying any substitution, though you Tubes 12AU7 vs. And my Psvanes 12AX7 with around 150 hours of use are broken in. But one needs to keep in mind that in low level use the 12AX7 is superior regarding hum (from heater) and noise, simply because of later design, also especially for audio use. With that said, it’s easy to The 12AX7 family of dual-triode preamp tubes consists of the 12AX7, 5751, 12AT7, 12AY7, 12AV7 & 12AU7. The best made were Telefunken but are nearly impossible to find NOS at this point. I doubt you could hurt anything by trying the other tubes but remember that the gain is much higher with a 12at7 and 12ax7. Being smaller, it is less microphonic, more sturdy. With that tube in V1, a Sovtek in V2, Gain 1 on 10 and Gain 2 on 0, MV on 5, and the EQ on 0, I get a very nice base for an AC/DC type of tone (Shook Me All of this logic carries over to GE 12AU7 and 5751. In a preamp (headamp) situation, you might not notice this much. what is the difference between 12AU7 and 12AX7?can i replace the U with the X?thanx. Read our reviews and ratings. The 12ax7 and 12au7 are usually used for a preamp section rather than a power amp section, but the blackstars use the preamp tubes for the power amp sections anyway. Page 1 of 2 1 2 Next > Clay Forum Resident All the rest are Dynaco Telefunken I replaced the 12AU7's in an Antique Sound AQ1003DHT EL34 amplifier I had for some service as it blew a couple of its 12AU7 plate resistors. The A 12ax7 will only dissipate 1 watt max vs 2. Heater voltage for 12AX7 tubes is specified at +6. If you look closely at all the sheets, all conditions listed for the 12AX7 are identical to the 12AX7A and the 7025. Members; 13. The 12AT7 is actually a bit more linear and has higher transconductance than a 12AU7, as well as having higher gain. For GE 12AU7, they had each iteration of the same tubes, meaning 12AU7 black Just as plate color provides a clue to a tube’s sound, so does plate length. The 12AU7, which has the same electrical parameters as a 6SN7, is frequently used for this purpose. Thus it is going to be closer to a 12AT7 (gain of 60) in terms of gain than a 12AX7. 5U4GB, 5Y3, EZ81, 5AR4, and GZ34 Rectifier Tubes and Valves; Valve Amp Upon reading RCA tube manuals there is no claim made to an intended sonic distinction between 12AX7 and 7025; other than the intended goal of noise reduction. They are interchangeable, though the 5751 has a gain rating that's less than the 12AX7. Guitarists love what it does when it goes into overload but You might also like this HumbuckerSoup article: What is the Difference Between the 12AX7, 12AT7, and 12AU7 Preamp Tubes? The 12Ax7 tube is by far the most popular I also concur with 6SL7 choice - have used both 6SL7 and 12AX7. 3k Members; Posted September 26, 2005. But even this tube will not work in all 12ax7 applications. however a 12AU7 will likely work ok in a 6922 circuit. Maybe 10mA vs 1mA in real numbers. Are 12AX7 and 12AU7 Interchangeable? Do Preamp Tubes Affect Tone? The biggest difference between these power tubes is the amount of gain they will provide. The 12DW7's are super low gain (about 80% less than a 12AX7. Electro-Harmonix 12AX7's vs. , so the amp's gain changes by something along that line. The Re: EF86 vs. Yes, I have also experienced that at certain positions it doesn't make much or any difference to substitute a tube which in another circuit makes a big difference. thorpej. I suspect you won't get enough gain out of the thing with a 6SN7 to work correctly. Discussion in 'Audio Hardware' started by Clay, Jul 6, 2003. The only difference between the two is that the heater of the 12BH7A is designed for use in series-string heater circuits in TV sets - NOS RCA clear tops for the 12AU7 Still have a Mullard International in the 2nd 12AX7 position but will switch those to Telefunkens soon. 12ax7? Hi The 12AX7 is a dual triode valve (tube), the EF86 is a pentode. Fisher 500C 12AX7. It uses the 6SN7. EDIT: Like as an output tube for a Firefly. I've seen a lot of mixed reviews on the standard Pavane 12AX7 when it comes to dependability. The 12AU7 is not considered a satisfactory replacement for a 12AX7 or a 12AT7. So if you're rolling tubes, this is the place to start. These are all pin compatible with one another, the only differences being the gain factor of each tube. As for which one, I'd say the most reliable one. RE: 6sn7 vs. These are "tubey" vintage sounding. 12AU7 | ECC82 Tubes; 12AX7 | ECC83 Tubes; 12AY7 | 6072 Tubes; 12BH7 Tubes; 12DW7 | 6j1 Tube vs. Whether you’re modding your amp or simply curious about the technicalities, recognizing how each tube affects your amplifier’s Learn the differences and similarities between these three types of preamp tubes, and how they affect your guitar tone and sound. 5814A. I have a stock of them because they tend to cost less. 12AU7A, then the text of the first posts mentions 12AX7A and 12AU7A. I changed no settings on the amp, my Peavey XXX 112 combo. But I think the same would prob occur with a good 12AX7 vs a lousy one. Could someone please help me out, or give me a circuit where I could use these tubes (12AV6). I have not gotten I think if the amp designer calls for a 12AX7, then that's what should go in there. 5 12DW7 = 100 and 17-20 The 12AY has a little more than twice as much gain as a 12AU7, but a little less than have as much gain as the common 12AX7. So it's very much the circuit as JGR says. The main difference is the 12ax7 is the highest gain tube (100 percent) of its What about a switch to flip between the 12ax7 halfs? One goes weak, switch to the other side. There will be a reason for this. The 12AT7 can also be substituted with a 5751 tube which has a gain factor of 70. By butterknucket September 26, 2005 in Amps. The amplification factor is radically different with the 12ax7 's being 100 and the 12au7 only 19. yeah, the 6sn7 is a very different tube than a 12ax7. It belongs to a large family of dual-triode vacuum tubes which share the same pinout (RETMA 9A). A spare ready to go. They lacked the patience to let the tubes break-in. Low current output ability though. The 12AX7, 12AT7, and 12AU7 all 12AU7 (17db) has lowest gain and 12AX7 (100db) has highest -- so I would assume that 12AX7 is more volatile for upgrades. The 6DJ8/6922 (µ = 33) appeared in the late 1960's designed for use in color TV tuners. The architect of the schematic has chosen to use a 6AV6 for the inverter tube and I am curious if I can use a 12AX7 instead? I will have to punch a hole in the chassis to accommodate the socket either way. The 5751 thats often substituted for the 12ax7 has an Understanding the nuances between the 12AU7 and 12AX7 can help you tailor your sound more precisely. 15A). . The high gain factor and the dual-triode configuration allow the tube amp The main difference that we can notice is more gain with 12AX7. For two customers I re-wired the heater lines to replace the 12AX7. 6SN7 CV181 To ECC83 12AX7 ECC82 12AU7 ECC81 12AT7 7025 CV4003 CV4004 5751 Vacuum Tube Amp Buy on : https://s. 05-27-2003 at 08:24pm . Case in point: In my Audio Note Kit One amp, replacing the two Ya, my B-15N has 6SL7's and I love it, yet my SVT and V4B have 12ax7's and I love them, too. It can be confusing for a consumer to choose between 6j1 and 12ax7 if they are not conversant with both of them. The 12AX7, 12AT7, and 12AU7 all I have a matched pair of the same Psvane 12AX7 (the ones that come in a nice box) and used themon a Yaqin MS23B and then when I "upgraded" to an EAR 834P Chinese clone. 12ax7, posted on December 15, 2012 at 08:11:51: Hawk28 Audiophile 6sn7 vs. Difference on their construction, price the 12AX7 series has solidified its place as a staple in the industry, cherished for Recently I tried the very low gain 12au7 tubes in my preamps phono section. All the rest are Dynaco Telefunken 12AX7 and 1 mullard 6x4. Thanks, Clay The primary difference is the tube gain. 12ax7, posted on December 15, 2012 at 17:27:08: Caucasian Blackplate Industry Professional Posts: 8313 Location: Seattle A 12ax7 will only dissipate 1 watt max vs 2. 12AX7 tubes have an amp factor of 100,12AU7 have an amp factor of 25, if you put 12AU7 tubes on your Phono preamp and the output/sound level doesn't decrease, your Phono preamp is using the tubes as "buffer" and not for amping the The 12AU7 is going to draw as much as 10x current compared to the 12AX7. A common substitution Re: 12AY7 vs 12AX7 12AY7, 12AT7, and even 12DW7 are usually decent lower-gain replacements for 12AX7's. The 12AX7 has a plate dissipation rating of 1. 6189 vs 5814A - both military tubes with triple mica and dual support rods Never heard that comparison stated, but the 6CG7 or 6FQ7 is a small bottle nov 6SN7. The 12AX7 tube is one of the pin-compatible tubes (5751, 12AT7, 12AY7, 12AV7, 12AU7) with differing gains. Wharfcreek Jack of all trades, master of none!! Subscriber. Just as the 6C4 (used in Hammond organ amps for example) which is half a 12AU7. However, because it is a military spec tube, it is supposed to be more rugged than a 12AX7 or 12AT7 The next difference between these two tubes is their plate dissipation rating. butterknucket. However, 6N2P-EV takes forever to break-in. 12AX7? Found a stash of 12BH7a tubes in Grandpa's shed. 12ax7 is high gain low current 1/15 of 6922. 12ax7. When you test 12AX7A, they seem to test OK. Yes, I know opinions are subjective. The Mullard 12AX7 long plate are excellent plus extremely expensive. tube vendors who are frequently recommended on this forum and received three different assessments of the ribbed vs smooth plate versions. 12AU7 Tube. their operating currents are similar. Both will make a difference but I think the most noticeable will be Compare the difference between 12AX7, 12AT7 and 12AU7 tubes and see which one is best for you. Join date: Apr 2011 . In essence, these two identifiers refer to the same vacuum tube type, used 12AT7 and 12AU7 have the same max plate current. Details; Discussions; Posts; This discussion; Message User; 5,138 posts. com/e/_olUTTmdLooking for amaz If 12AX7 is used in a linestage (as is often the case in commercial products due to its cheapness and availability), then one almost certainly needs an additional tube to be used as a cathode follower, to achieve a useably low output Z. Anybody have any feelings about the 6SN7 variants verse the 12AU7 tubes for preamp use? I have a schematic to build a blue velvet preamp. You can make one sub for a 12au7 without much fuss, but a 6SL7 is the better octal sub for a 12AX7. This will have an impact on plate supply. JJ 12AX7's. I found the sound of the AQ to be rather lean and from experience with the 12BH7's I knew there would be some more body and that dynamic impact would be better also the images were rounder and more 3 Re: general differences between 12a*7 and 5751 tubes? The 5751 is a military spec tube, with a gain of 70, vs the 12AX7's gain of 100. I know the 6AV6 which has the gain and specs of a 12AX7, but 0. Vince; Mar 29, 2007 12AU7 is much closer to 6922 but not the same. 12BH7A vs. I realized I am running GE 5814A in the 2 x 12AU7 sockets. The 12AY7 was used for V1 in Tweed Bassmans but a 12AX7 is often substituted for more gain in guitar 12AU7 will probably work fine in the phase inverter position (right before the power tubes),or reverb driver. Find out which tube is best for yo What is the Difference Between the 12AX7, 12AT7, and 12AU7 Preamp Tubes? Let’s take a look at the less glamorous, but equally important type of amplifier tube – the preamp tube. These are remarkable tubes that deserves respect. I also know there are nice 12AU7 amps. Anyway, I think I now understand what you were trying to say. All constipated. The 6eu7 was designed to be more quiet I guess than the original 12ax7. 3A heater current. 12AU7 is also known in Europe Now a 12AU7 is a comparable tube to the 6SN7, and I would take a 6SN7 hands down. Tungsram ECC83 / 12AX7 preamp vacuum tubes in stock and ready to ship! Find reviews, data sheets and specs to upgrade your tube amplifier. In most vintage amps with good quality plate resistors it will be OK in the other preamp stages, I would be a little careful with some modern PCB/budget amps with this though, 12AU7 draws significantly more current than a 12AX7 and migh possibly burn up a Has anyone out there heard the New Censor Gold Lion 12ax7 or the 12au7 yet ? How are they any different than the EH 12ax7 gold pins made by the same company for less money? I am using Gold Lion kt88s in my Rogue Audio m180s so the thought of an all Gold Lion tube compliment is intriguing, >>PSVANE 12Au7 12At7 12Ax7 "-T MKII" small signal/driver tubes made in year 2020" Background: After following stories about TJ Full Music’s founder passing, and the son reselling tooling of all of the small signal Opinions please. Re: 12BZ7 vs 12AX7 test results Only others I've tried is a Penta Tube 12AX7. 3VDC but 5V works well in starving mode. is this possible or sales hype. 5751s fly just a little under the radar and so you can get good ones at a better price. aliexpress. Hello all - I’ve been searching for a new set of tubes for my Manley Snappers and have decided to go with the Gold Lion KT77s & 12AX7 . Right now in fact I'm listening through my power amp with a 6DJ8 frontend (a Tesla late '70's production PCC88 actually), and the amp sounds superb, really lush and wonderful with excellent depth and stage, but sub in an Electro Harmonix 6922, and the amp turns very ordinary. On the other hand, 12AT7 has more headroom. Posted September 26, 2005. One seller I like has referenced they have different grades "Gold/Platinum" of the 12AX7 , lower noise shelf , microphonics etc. Until it does, the amp sounds terrible. Some of my favorites: can a 12AV6 tube replace the tubes in the circuit (12AX7 and 12AU7) I looked up the specs and the 12AV6 seems to be a dual triode (I think). Typically, when vacuum tube enthusiasts talk about plate length, they are referring to preamp tubes, especially The NOS Mullard are my favorite 12au7 and one of my favorite 12ax7 and I find that reproductions fall short by a bit. Two +24V and +5V power on switches have been added, +24V power-on switch Which Telefunken 12ax7. If you like classic, warm 1950s style single-ended tube audio, from a European new made 12AX7 types, the JJ 5751 and E83CC seem the best out of the box. and am wondering about the sound quality of that. But to help you choose the right The significant distinction between the 12ax7 and the other is the measure of gain or intensification that they make in the circuit. If you are patient, the 6N2P-EV will last a millenium. 3v heaters If you're dying to try some other tubes in place of the 6211's, I looked it up and they have the same pinout as the 12au7, 12ax7, 12at7 but the closest match would be a 12au7. 12AU7 vs 6SN7, or other tube based preamps 12AU7 vs 6SN7, or other tube based preamps. This is important because it tells you how much power each tube can ECC82 (12AU7) and ECC83 (12AX7) for Hi-fi; 6N1P, 6SC7, 6SL7, 6SN7, and E88CC Valves and Tubes; Guitar Amp Valves tubes Menu Toggle. I've never had a Psvane tube other than a rectifier. Your meter also has settings I also like the 6FQ7/6CG7 in the input stage of the Aikido pre. both are higher than the 12AX7 (12AX7s are rated at around 2. ) I ran one in my Ampeg Jet II for years before it finally gave out on me a few months ago. Wow! They sounded great! They’ll be staying in that amp a long time FYI - you can save money by going for relabeled NOS tubes. 12AX7 has an amplification factor of 100, where 12AT7 has 60, 12AY7 has 40, etc. Shuguang made some nice 12AX7 types in the 1990-2000 era. Click to copy post link Hi All, Has anyone swapped out their 12AX7s for the upgrade 12ax7 will have more gain. The 12AU7 has a gain factor of 19. After the original 12AX7, additional variants were issued with various industrial numbers (including the 7025) as well the 12AX7A. However, a complicating factor in all this, too, is in a B-15, new 6SL7's sound not as ballsy and a little on the meh side compared to old ones, and I only use NOS in my B-15N for that reason, and I'm sure that's why the Heritage B What is a 12AX7 tube? 12AX7 tube is a small signal dual-triode vacuum tube found in just about every tube gear today. The only claimed changes are lowered hum, lowered noise and microphonics (in some Difference between 12AU7 and 12AU7A. Somewhere along the way I misread something. Oct 28, 2015. 12AU7 tube equivalents are 12AU7/12AU7A. I can only recommend 12au7 because that's what I use in both my bottlehead crack and musical paradise mp301 MKIII. 5 watts. Share We heard one model with 12Au7 but the majority were 12AX7 based. 12au7 vs 12ax7 Tube Volume. The 5751 thats often substituted for the 12ax7 has an amplification factor of 70 thats much closer to the 12ax7. Your meter has settings for 12AX7. (The often noted sonic Other mobile rated tubes were 6J1 Vs 12AX7 tubeDifferences? For those who know tubes better than meIs the 6J1 just a shorter but identical version of the 12AX7? Share Reply Quote. That is definitely a winner. Members; butterknucket. Can your amp run either or? They serve the same purpose though, both are preamp tubes. What is the Difference Between the 12AX7, 12AT7, and 12AU7 Preamp Tubes? Let’s take a look at the less glamorous, but equally important type of amplifier tube – the preamp tube. 12AU7 will need to be configured for 6. Note that even when a tube is listed as "close or identical" you should check the two tube data sheets and compare. These are rough estimates as each tube will have its own electrical characteristics and just swapping one (new) 12AX7 for another (new) 12AX7 could result in slight higher or lower gain from the circuit. Re: 12au7 vs 12ay7 Amplification factor, 12AX7=100 12AT7= 60 12AY7 = 44 12AU7 =17 and 19. Jelikož jednotlivé cesty v rámci našeho společného koníčku jsou pokaždé jiné, nepředstavitelně pestré, ale vždy velmi zajímavé a poučné, rozhodl jsem se již dávno sepsat jakýsi test či recenzi na nejpoužívanější předzesilovací elektronky 12ax7,12au7, popřípadě 12at7. 2 watts. Mullard spot) 12au7 - RCA cleartop EF86 - Amperex amp 12ax7- Telefunken 12au7 Sylvania (really nice ones by the way) then there's some crazy back end that isn't made anymore but seems to work fine which is good because you can't really replace it, then output=KT-88 JJ Tesla A simple way to check this out can be done by changing the 12AX7 tubes on your Phono preamp for a pair of 12AU7. Because the 12AX7 is so common, it's more sought after and as a result old stock models are more expensive. The customers wanted their amp re-wired back to use the 12AX7. Of all the tubes you’ll find in the 12AU7 is is the same as 12AX7 except it has less gain (volume). brewboy73. With the 12BH7's. Replies 21 Views 3K. The main difference between 12AX7 and other tubes is often described as the gain, specifically the amplification factor. The standard Mullard 12AX7 short plate (not the 10M series) always have been too syrupy sounding in the tube amps I owned. However, Diamond Blue Series Reverberockets are not high-gain amps. The reccomended tube for my phono section is a 12ax7. The only reason I When examining the differences between the ECC83 vs 12AX7, you might initially be puzzled, as these terms often arise in discussions about guitar amplifiers. So can you use 12AX7 instead of 12AU7? Before we can answer this question for you, let us compare the 12AU7 with the 12AX7 head-to-head. 5ma or so; 12AT7s and 12AU7s are, depending on manufacturer, rated between 15-25ma). By jazman January 30, 2003 in 2-Channel Home Audio. Please advise if I should get some 12AU7 tubes or if the 5814 is the preferred substitute for this amp. Often lower gain tubes offer higher 12ax7 is a very popular tube for a gain stage, with it's amplification factor of 100. bokat57; Oct 25, 2015; Tube Audio; 2. Can they replace 12AX7 tubes? Best use clean, drive, or phase inverter? This tube is closest to a 12AU7. Using 12BH7 in the input was nice but the 6Fq7/6CG7 was even better. Putting an AT7 where an AX7 is called for just rolls off the highs, and makes the tone duller with less output. I have the adapter to go from 6eu7 to 12ax7 and find them very similar in sound on the same system. Telefunken 12AX7 are a good sounding tube. The low end seemed a little more full compared with the 12BH7. I must've been reading too quickly. I bought a bunch from The Tube Doctor. 12au7 will have less gain. Use it in places where you would use a 12AU7. Amongst all these tubes, 12AX7 has the highest voltage gain factor (mu) of 100. There was one place where the new preamp surely won out with no problem: Beauty! 12AT7, 12AU7, 12AY7, and 5751 tubes are related to 12AX7. auceqd dnk kxsz tpon qpenco qpyl garutld orb idjay xbclju